Source for Block Board: Blockboard is made up of a core of softwood strips. These strips may be up to about 25mm wide. The strips are placed edge to edge and sandwiched between veneers of hardwood. The sandwich is then glued under high pressure. Blockboard is not suitable for outdoor use because the glues used are interior glues. Sizes: Blockboard is sold in sheets of 2440 x 1220mm and are normally 30mm thick.

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